To address the problem that joints would exceed limitation in motion control of Tele-operation, a novel efficient inverse kinematics method for the 7 DOF manipulator of the thermonuclear fusion reactor to trajectory planning is presented in this paper. Based on Weighted Least-Norm (WLN) solution, the fixed joint angle inversion method is applied to decrease the accumulated error and avoid joint limits. Simulation results illustrate the effectiveness of the proposed algorithm on avoiding joint limitation and reducing the tracking error.